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Facts about The Saint Lawrence River For Kids


The Saint Lawrence is a large river flowing approximately from southwest to northeast in the middle latitudes of North America, connecting the Great Lakes with the Atlantic Ocean. The river traverses the Canadian provinces of Quebec and Ontario and forms part of the international boundary between Ontario and New York in the United States.

  • The Saint Lawrence River originates at the outflow of Lake Ontario between Kingston, Ontario, on the north bank, Wolfe Island in mid-stream, and Cape Vincent, New York.
  • From there, it passes Gananoque, Brockville, Ogdensburg, Massena, Cornwall, Montreal, Trois-Rivières, and Quebec City before draining into the Gulf of Saint Lawrence, one of the largest estuaries in the world.
  • The estuary portion begins at the eastern tip of Île d’Orléans, just downstream from Quebec City.
  • The farthest headwater is the North River in the Mesabi Range at Hibbing, Minnesota.
  • It encompasses four archipelagoes: the Thousand Islands chain near Kingston, Ontario; the Hochelaga Archipelago, including the Island of Montreal and Île Jésus (Laval); the Lake St. Pierre Archipelago (Classified biosphere world reserve by the UNESCO in 2000) and the smaller Mingan Archipelago.
  • It is the second longest river in Canada.
  • The Saint Lawrence River is in a seismically active zone where fault reactivation is believed to occur along late Proterozoic to early Palaeozoic normal faults related to the opening of Iapetus Ocean.
  • The Saint Lawrence Valley is a physiographic province of the larger Appalachian division, containing the Champlain and Northern physiographic section.
  • Though European mariners, such as John Cabot and Alonso Sanchez in the 15th Century and the Norse 500 years still earlier, explored the Gulf of St. Lawrence the first European explorer known to have sailed up the St. Lawrence River itself was Jacques Cartier, during his second trip to Canada in 1535, with the help of Iroquoian chief Donnacona’s two sons.
  • Until the early 17th century, the French used the name Rivière du Canada to designate the Saint Lawrence upstream to Montreal and the Ottawa River after Montreal.
  • The Saint Lawrence River served as the main route for European exploration of the North American interior, first pioneered by French explorer Samuel de Champlain.
  • Having captured Louisbourg in 1758, the British sailed up to Quebec the following year thanks to charts drawn up by James Cook.
  • An extensive system of canals and locks, known as the Saint Lawrence Seaway, was officially opened on 26 June 1959 by Queen Elizabeth II (representing Canada) and President Dwight D. Eisenhower (representing the United States).
  • From source to mouth, the names are: North River Saint Louis River Lake Superior Saint Marys River Lake Huron Saint Clair River Lake Saint Clair Detroit River Lake Erie Niagara River Lake Ontario Thousand Islands Saint Lawrence River The Saint Lawrence also passes through Lake Saint-Louis and Lac Saint-Pierre in Quebec.
  • In 1980, Jacques Cousteau traveled to Canada to make two films on the St. Lawrence River and the Great Lakes, Cries from the Deep and St. Lawrence: Stairway to the Sea.